On the Effect of Channel Impairments on VANETs Performance

The primary means of studying the performance of vehicular ad hoc networks (VANETs) are computer simulations. Nowadays, the development of analytical models and the use of hybrid simulations that combine analytical modeling with discrete-event simulation are of great interest due to the significant reduction in computational cost. In this paper, we extend previous work in the area by suggesting an analytical model that includes distance-dependent losses, shadowing and small-scale fading. Closed-form expressions for the packet reception probability and the packet forwarding distance in the absence of simultaneous transmissions are presented. Numerical simulations validate the proposed formulation. The impact of path loss and fading on network throughput is explored. Interesting results that shows the efficacy of the approach are provided. The derived formulation is a useful tool for the modeling and analysis of vehicular communication systems

Dienstbasierte Kommunikation über unzuverlässige drahtlose Verbindungen für selbstorganisierende Sensor-Aktor-Netze

Die in dieser Arbeit vorgestellte ServiceCast-Architektur umfasst Lösungen zur dienstbasierten Adressierung und Kommuikation in drahtlosen Sensor-Aktor-Netzen. Besondere Beachtung kommt der realistischen Repräsentation und Kalibrierung des indeterministischen drahtlosen Kanals in Simulationen und dessen Auswirkungen auf Mechanismen höherer Protokolle zu. Diesen besonderen Randbedingungen wird durch neue Formen der Adressierung und Zustellung von Daten (z.B. Somecast) Rechnung getragen